Such a portable working machine is normally carried by an operator in operation with the machine, and its weight would be a considerable load to the operator's arms. To alleviate the load to the operator's arms, shoulder harnesses are used. These shoulder harnesses, in general, are configured to surround the chest of an operator, and composed of a harness network that includes at least a back-fitting member to be worn on the operator's back, and right and left shoulder belts connected to the back-fitting member.
FIG. 6 schematically illustrates a shoulder harness disclosed in Patent Document 1, which is referred to as a first existing harness hereafter. The first existing shoulder harness 1 shown in FIG. 6 includes a side-fitting belt 11 connected to a back plate (back-fitting member) 2, and the side-fitting belt 11 joins at the front end thereof with distal ends of right and left shoulder belts SB in front of the operator, thereby forming a harness network 4. The side-fitting belt is a member that should fit one side of an operator's chest when the operator wears the shoulder harness. In connection with the harness network 4, a hook 8 as a hanging element is held on a hip pad 5. A working machine (not shown) can be removably held in engagement with the hook 8. More specifically, a laterally extending tunnel-like guide 5a is provided near the upper end of the hip pad 5. A suspension string 6 is inserted to pass through the tunnel-like guide hole or loop 5a is, and one end thereof is connected to the back-fitting member 2. The opposite end of the suspension string 6 is connected to the side-fitting belt 11. The hip pad 5 is also connected to the back-fitting member 2 via a suspension belt 7 that acts as a second suspension member.
FIG. 7 schematically illustrates a shoulder harness disclosed in Patent Document 2, which is referred to as a second existing shoulder harness hereafter. The second existing shoulder harness 10 shown In FIG. 7 has a harness network 13 including a first diagonal belt 11A that is connected to an upper end portion of a back-fitting member 2 and extends therefrom diagonally. The first diagonal belt 11A extends from the upper end of the back-fitting member 2 diagonally downward along the left side of an operator's chest until reaching a front portion of the operator, and joins the waist belt 12 there. Thus, the first diagonal belt 11A substantially acts as a side-fitting belt. The waist belt 12 extends across the back-fitting member 2 to include an extension 12a that is a part beyond the back-fitting member 2 and extends along the right side of the operator's body. The extension 12a is connected at the right front end thereof to a second diagonal belt 11B that extends diagonally from the upper end of the back-fitting member 2. A hook 8 held on a hip pad 5 is connected to the harness network 13 via two suspension belts 14 and 15, front and rear. More specifically, the front suspension belt 14 is connected to the juncture of the first diagonal belt 11A and the waist belt 12, while the rear suspension belt 15 is connected to the juncture of the extension 12a of the waist belt 12 and the right one of the shoulder belts SB.
FIG. 8 schematically illustrates a shoulder harness disclosed in Patent Documents 3 and 4, which is referred to as a third existing shoulder harness hereafter. The third existing shoulder harness 20 shown in FIG. 8 includes a waist belt 3 and a side-fitting belt 11 connected to a back-fitting member 2 such that these three elements make a harness network 21. A hook 8 held on a hip pad 5 is connected to the harness network 21 via two suspension belts 14 and 15, front and rear. The front suspension belt 14 is connected to the front end of the side-fitting belt 11, while the rear suspension belt 15 is connected to the back-fitting member 2. As shown in FIG. 8, the shoulder harness 20 further includes a releasable joint buckle 16 that is to be positioned on the breast of an operator.
FIG. 9 schematically shows a shoulder harness disclosed in Patent Document 5, which is referred to as a fourth existing shoulder harness hereafter. The fourth existing shoulder harness 30 shown in FIG. 9 includes a back-fitting member 2 and two side-fitting belts 31 and 32, right and left, which are connected to the back-fitting member 2 such that these three elements make a harness network 33. A hip pad 5 having a hook 8 thereon is connected to the harness network 33 via two suspension belts 14 and 15, front and rear. The front suspension belt 14 is connected to the front end of the side-fitting belt 31, while the rear suspension belt 15 is connected to the back-fitting member 2.